Mitsubishi Fuso's hybrid concept dump truck

October 27, 2007 Mitsubishi Fuso Truck and Bus Corporation (MFTBC) has unveiled the “Canter Eco-D” hybrid concept dump truck at the Tokyo Motor show. The truck delivers extremely low emissions and quiet performance while incorporating a host of advanced features. With a 3350 mm wheelbase the Canter Eco-D is capable of carrying a 3000 kg dump body. Its potential uses include light construction, road repair and landscaping. With its hybrid drive and emissions control system, the truck is designed to achieve significant reductions of nitrogen oxide (NOx) and particulate matter (PM) over conventional diesel-only-powered vehicles.

The central components of the Canter Eco-D’s hybrid system are a 3-liter DOHC diesel engine (92kW); an ultra-slim electric motor/generator (35 kW); a high performance Lithium(Li)-ion battery; and the INOMAT-II automated mechanical transmission. The Canter Eco-D adopts a similar parallel hybrid system that is already offered in the Canter Eco Hybrid light-duty truck, in production by MFTBC since July 2006. In a parallel hybrid system, the power to drive the vehicle comes from the vehicle's electric motor, the diesel engine or both. Fuel efficiency and emissions reduction are achieved by using them singly, or in combination with each other according to driving conditions.

The hybrid system switches its operational mode according to the driving situation. The electric motor is used to drive the vehicle when starting off. During hard acceleration, both the diesel engine and electric motor/generator power the vehicle. When cruising, the vehicle is driven by the diesel engine only, like a conventional vehicle. When slowing down or braking, the electric motor/generator functions as a generator to brake the vehicle. The generator converts brake energy into electric energy and stores it in a Lithium-ion battery for the next acceleration. This arrangement contributes to maximum fuel efficiency and reduced emissions.

A unique feature of the Canter Eco-D is its use of the electric motor for the power take-off to operate the dump body. A power take-off is a mechanism used in special purpose trucks for diverting power from the truck’s engine to drive auxiliary equipment. In the Canter Eco-D, the electric motor is utilized to provide energy for the power take-off to raise and lower the dump body. This approach significantly reduces emissions and noise, as the engine is not required during this operation. MFTBC imagines this hybrid/power take off arrangements could also be extended to other types of special purpose vehicles, such as lifts and cherry pickers.

“The new Canter Eco-D is a view to future possible applications of hybrid systems and other advanced technology in commercial vehicles,” explained Tsutomu Kondo, MFTBC Senior Manager and Head of Hybrid Electric Vehicle Development. “In addition to delivery trucks, Mitsubishi Fuso believes hybrid technology can also be successfully applied to light-duty dump trucks and their numerous uses, particular those working in urban locales. The Canter Eco-D is a vision of this thinking. At the same time, this truck incorporates numerous advanced concepts for commercial vehicle styling, safety and functionality.”

MFTBC have also developed the Cantor Eco-D with an eye on safety. A large, overall increase in glass area over previous cabins enhances the driver's field of view, and makes it significantly easier to visually confirm safety. Also optimizing field of view is an increase in the angles of the front of the truck and the instrument panel, thus successfully reducing low front blind spots from the driver's seat. The blind spot has also been minimized by using a truss structure for the front pillar.

The roof above the driver's seat and passenger seats utilizes a special material incorporating a carbon graphite weave that is light but very stiff, designed to provide a high degree of safety for cabin occupants.
Also, in addition to ABS for preventing wheel-lock-up under braking, there is an ESP system to prevent the vehicle from slipping sideways.

Operation of the dump body itself is also optimized for safety. The controls for raising and lowering the dump body are located on the overhead console inside the cabin. CCD cameras are fitted at three points to enable driver/operator to monitor the area to the rear and the areas to the sides of the truck. The views from the cameras are displayed on monitors installed in the rear-view mirror section inside the cabin. MFTBC claim that combining visual confirmation of safety with monitoring of the views of the truck's surroundings displayed on the monitors provides greater safety when operating the dump body. The feeds from the three CCD cameras also function as side mirrors and a rear-view mirror.

For ease of operation, there are also dump body controls on the outside of the vehicle. The control logic for these external switches incorporates a fingerprint recognition system with safety locks that prevent the controls from responding unless the system identifies pre-registered fingerprints. This approach has the benefit of enabling push-button operation of the dump body while preventing accidents resulting from ease of operation by unauthorized operators.

The distinctive styling of the Canter Eco-D has also been designed with practicality in mind. Skirt-shaped side covers incorporate a battery cover with distinctive blue LED illumination, which has been adopted to enhance safety and make the truck more visible at night. The front and rear wheel arches are designed to minimize gaps between arches and tires, controlling the scatter of pebbles and other debris kicked up by the tires, while both front and rear suspension are given lift-up functionality so that the truck body can be raised by 70 mm for ease of maintenance or tire changes so the small-gap design does not hinder work on the tires and wheels.

The cab structure also is optimized for functionality. The side doors utilize the whole of the side panel, and are hinged at the rear to makes it easy to get in and out of the cabin at narrow door angles - particularly useful when working in restricted spaces. The expansive glass roof above the driver incorporates a state-of-the-art liquid crystal laminate that adjusts the level of sun screening in line with the strength of the sunlight. In addition to regulating the proportion of light transmitted, harmful rays are cut in proportion to the levels of infrared and ultraviolet light. This provides fine control of the cabin temperature, and contributes to energy saving by optimizing air conditioner usage, even when working under a hot sun.

The merging of style and functionality extends to Canter Eco-D’s dump body with an upper/lower split built into the tailgate. When the dump body is tilted, standard designs fully open the entire tailgate at once according to the tilt angle, but the Canter Eco-D's split tailgate detects the weight and type of the load and controls the opening angles of the upper and lower tailgate sections separately with internal motors in order to minimize load scatter to the rear. The dump body slopes internally, ensuring that the load can be dumped smoothly.

“The numerous advanced design ideas incorporated in the new Canter Eco-D are expected to inform concepts for Mitsubishi Fuso vehicles of the future, especially light-duty dump trucks,” said Mr. Kondo. “MFTBC is committed to reducing the environmental impact of commercial vehicles. Our vision is for ever more environmentally-friendly trucks and buses that also enhance safety and provide maximum driver and customer benefits.”